ABS Technical Question 98+

[wb4lbg]

Here's a highly technical question about the ABS on 98+ Rodeos.

The sensors on the front wheels act like proximity probes producing pulses as the wheel turns. What exactly is the probe looking at? Is it something on the front axle or something on the brake rotor? Or is it something else?

Thanks!

[rodeo02]

The probes, or poximity sensors read the 'teeth' on an exciter ring that is bolted to the inside of the brake rotors. Basically the sensors want to count those teeth at EXACTLY the same speed. The slower spinning ring (wheel) will get it's brake fluid pressure automaticlly modulated by the ABS pump, in an attempt to get all wheels spinning at the same rate. The sensors are mounted thru the backing plates and the exciter rings have to be removed and replaced on new rotors.

G/luck
Joel

[wb4lbg]

Thanks for the reply, Joel. So the exciter rings don't come with the rotors -- that's the info I was digging for. One of my exciter rings is missing some teeth (long story) and I didn't know whether I needed to buy a new rotor, a front axle unit, or what.

I bet this is a dealer only part. I'll give Merlin a call on Monday.